Growth hormone, insulin-like growth factor I, and leptin interaction in human cultured lutein granulosa cells steroidogenesis

Abstract

To investigate the effect of leptin on the actions of growth hormone (GH) and insulin-like growth factor-I (IGF-I) in ovarian steroidogenesis in vitro. In vitro cell culture study. Research laboratory of a university hospital. Luteinized granulosa cells (GC) were obtained from 20 healthy women undergoing ovarian stimulation for IVF treatment. Granulosa cells were cultured in serum free conditions for 72 hours with either GH or IGF-I, or their combination, in the absence or presence of leptin (1, 10, and 100 ng/mL). At 24 and 72 hours of the culture estradiol (E(2)) and progesterone (P) concentrations were measured in culture supernatants by enzyme immunoassays. Leptin at the doses of 1 and 10 ng/mL significantly stimulated, whereas at the dose of 100 ng/mL it significantly suppressed E(2) and P production as compared to control. Estradiol production was significantly stimulated by both GH (72 hours) and IGF-I (24 and 72 hours) and that of P only by IGF-I (72 hours). Leptin at the low doses enhanced, whereas at the high dose it suppressed the effect of GH or IGF-I on E(2) and P synthesis. These results demonstrate for the first time that leptin can modulate the effect of GH on steroids production by human luteinized GC in culture.